What do you think about "e-soaring"?

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henryk

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You are proposing this?

View attachment 106395
=dr Sorokodum =scientist,experimenter...

=possibility to get NEGATIVE drag (THRUST force) !

BTW=dr Schmid (Germany) was ivestigatet this mode of airtansport,
but small effect (quasistationary aerodynamic ,dr involve,is not anoth
to explain this fenomenon).


prof.Platzer article,based on dr Sorokodum investigation results...

dr Sorokodum works with help of nonstationary,nonlinear aerodynamic...
=much more complicated versus "us", stationary.
 
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blane.c

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Well we all know there is no free lunch. So the wing oscillates through the air? Like a snake? What pushes the oscillations? It is easy to see a wing oscillating on the sea floor will extract energy but not so easy to see it using energy strapped to a helicopter chassis.
 

henryk

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henryk

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Like a snake?
=NO !=by proper vortices generation...(birds and buts like).


=dr Jerzy Wolf (Warsaw) was explored "OSCILLATING wing propulsion",
snake like...

in 1977 He was fly horisontally on his Z-77,with rubber harnesse !

=I want made similar with 15 kg KASPERwing (SKOWRONEK=lark)

 
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blane.c

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So it will take some time to look at this over to gain some concept of it. But you say this is a primitive? What would make it better?
 

jedi

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Henryk,

FYI Before Jerzy Wolf AIAA paper No. 74-1928 MIT 1974 There was NASA Report CR-2315 1972 “Pseudo-Ornithopter Propulsion” by Grant Smith. Also presented at MIT Technical Soaring Symposium in 1971 if I remember correctly. It is reference number 7 of the above referenced J Wolf paper.

I believe this paper resulted in the development of the Trampofoil and Aqua Skipper. Development work starting with Paul B. MacCready Jr. (Paul MacCready - Wikipedia) and his two boys work on a hydrofoil boat propelled with an oscillating hydrofoil .
 

John.Roo

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I will blow hard later (have to put in floor in bathroom first).

Well I've been thinking there is much to do about nothing as far as asymmetrical thrust goes on the one hand because the power needed for these machines is so minimal in the first place divided by three it is hard for me to imagine that anyone is really going to have much issue controlling it. That said however rudder trim becomes obligatory because holding pressure becomes a nuisance. It is easy for me to imagine two smaller motors used primarily for take-off and climb then props stopped and a center motor for sustain. If the center motor is roughly twice the power of the asymmetrical motors then they would have even less influence on yaw.

Of course the sailplane could start manifesting warts like a Toad, it would have to be done inventively not to be visually disturbing.
I am not against your point of view.
In USA is experimental category still popular and you need PPL to fly experimental. In Czech Republic is situation different - we have only very few experimental airplanes and is not easy to register new plane as experimental. So I have to follow UL-2 rules issued by LAA. They give me a lot of freedom (MTOM 600 kg, stall speed 83 km/h, no limit for engine power etc.) but also some limitations. I cannot discuss with inspector that in case on failure "...is hard for me to imagine that anyone is really going to have much issue controlling it". I just have to show that opposite motor will automatically stop as well.
Before we start to design airplane we have to follow rules and we have to look also to other EU countries what they allow in UL category. So finally I am facing even more limitations. UL pilot license is affordable = very popular.
Following my "keep it simple" rule makes my sitution easier.
Unfortunatelly it also means less dream designs....

So.... yes, you are right that two small electric motors + one IC engine is OK. You are also right that even assyymetric thrust situation should be handled by pilot with standard skills. I pragmatically say - for tandem propulsion configuration would be easier to get permit to fly :)

But here on HBA we can dream even about "oscillating thrusters" or "multi motor propulsion". I have no problem with that :cool:
 

blane.c

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I am not against your point of view.
In USA is experimental category still popular and you need PPL to fly experimental. In Czech Republic is situation different - we have only very few experimental airplanes and is not easy to register new plane as experimental. So I have to follow UL-2 rules issued by LAA. They give me a lot of freedom (MTOM 600 kg, stall speed 83 km/h, no limit for engine power etc.) but also some limitations. I cannot discuss with inspector that in case on failure "...is hard for me to imagine that anyone is really going to have much issue controlling it". I just have to show that opposite motor will automatically stop as well.
Before we start to design airplane we have to follow rules and we have to look also to other EU countries what they allow in UL category. So finally I am facing even more limitations. UL pilot license is affordable = very popular.
Following my "keep it simple" rule makes my sitution easier.
Unfortunatelly it also means less dream designs....

So.... yes, you are right that two small electric motors + one IC engine is OK. You are also right that even assyymetric thrust situation should be handled by pilot with standard skills. I pragmatically say - for tandem propulsion configuration would be easier to get permit to fly :)

But here on HBA we can dream even about "oscillating thrusters" or "multi motor propulsion". I have no problem with that :cool:
Yes I know, I am crazy man, woot woot. You could put three motors in a row, one tractor, one pusher and one in the tail. But you would really have to want to do it.

But more realistically if you did want to consider two motors you could put them both in pusher by making the aft motor hollow shaft and forward motor shaft goes through it. Then forward motor turns counter rotating aft pusher propeller and aft motor turns the propeller slightly in front of it.

Going extreme you could use the same arrangement on the front in tractor and end up with four in a row.

"By crackie" you could put four more under the same principle in the tail and have eight in a row.

The only reason for more than one though on a glider is if it is intended for touring across inhospitable terrain were loss of a single sustainer could put you out of gliding range of a suitable place to land whether it be geographical or geopolitical.
 

blane.c

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Владимир Топоров,(in Tajga winter own Laboratory)...

BTW=his man powered ORNITHOPTERs are much better as all another
constructions in the World !!!


"2.10. Волнообразный полёт "

>20 % gain in "weavy trajectory fly"
Interesting, I will not pursue this avenue personally. There seems to me to be inadequate stability and it looks uncomfortable.

The Volerian by looking at it may have stability issues as well, how would it be stable in gusty conditions? You know it's ability to recover from upset? The stability about the vertical and longitudinal axes is concerning to me lateral may be okay.

Also the Volerian, icing, rain? It seems like a nightmare to protect from icing and I am not sure of the science to know how it would be affected in the rain.
 
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henryk

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Also the Volerian, icing, rain? It seems like a nightmare to protect from icing and I am not sure of the science to know how it would be affected in the rain.
-I am afraid,of the VOLERIAN Specific Thrust (energy consumption)...

=birds are not to sensitive to rain ...?

(his fathered wings are not laminar.)
 
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